Tape fullness

[brackovic]

Hi,

The customer has new set of LTO Ultrium tapes with capacity of 200/400 GB.
Several different groups have been defined and different level of fullness appears in various groups. In Oracle group (group with NMO) tapes are used as is expected, i.e. tapes from adequate pool have 292 and more GBs and still are appendable.
On the other side, tapes from the pool for file system have much less data (115 GB, 124 GB, 120 GB) and all of them are full.
All tapes are from the same package, hardware is same, all clients have enabled directive NT standard with compression.

What could be done in this case to enforce system files backup to use compressed capacity of used tapes?
Due to the nature of files in file system backup, customer expects to use at least 300 GB of each tape.

S

 

[605]

NetWorker always appends data to a tape until it has reached the End-of-tape. Depending on how much the data can be compressed, it can store much more than the native capacity - this especially applies to databases.

However, if the program can not recover from a write error, NetWorker, as a precaution will set a media to full, preventing the occurance of more such problems for this media. Do not forget that up to this point, there could be an excessive numbers of write retries which will not allow to reach the expected capacity at all.